基于AVHRR﹑MODIS和MVRIS数据的辐射雾变化检测与分析

以过境时间不同的NOAA-16/AVHRR、NOAA-17/AVHRR、FY1-D/MVRIS、TERRA/MODIS和AQUA/MODIS五种遥感影像数据组成一组序列影像,对发生在湖北省2005年2月4日的辐射雾进行了一次变化检测与分析.经地面验证,序列影像数据在雾变化检测的研究方面具有很大的潜力,检测结果动态地显示了该次大雾的形成﹑发展﹑稳定﹑消散的过程.将检测结果与该区域的DEM和水系矢量图结合分析发现,二者在辐射雾的变化发展过程中起着非常重要的作用.     

阳光于丹不怕老

穿平底鞋,常蹦着走,累了就玩,少说消极话4月14日午后,著名学者于丹走进了人民日报社大院,应邀主讲"世界读书日"之青年讲堂的首场讲座。在这个春花烂漫的时节,于丹微笑着坐在怒放的梨花下,与记者聊起了自己的生活与健康心得。     

一对治沙父子的生死接力

在我国治沙大军中,有这样一对父子——父亲是赫赫有名的全国治沙英雄石光银,儿子是治沙的后起之秀石战军。在陕西定边毛乌素沙地边缘,父子二人共同谱写了一曲人进沙退的壮歌。老石以毕生的治沙经验培养着儿子,石战军则不负重托,干得有声有色。然而,就在老石可以把自己的治沙事业托付给儿子时,一场车祸夺走了石战军年轻的生命。经历了丧子之痛,老英雄又一次坚强地回到了治沙第一线,这一次,他肩上承载的是两代人的治沙理想。人进沙退,绿锁黄龙。中国林业发展到今天、治沙成果如此显著,正是因为有无数石家父子这样的人,一代接着一代干,甚至不惜献出宝贵的生命。他们用汗水和热血在茫茫沙地浇灌出片片绿荫,铸就了加快现代林业发展的坚实基础。     

浓浓春意慢慢品

阳春三月,春光明媚,与北国"白雪却嫌春色晚,故穿庭树作飞花"的景象相比,江南已是一片春意盎然。     

ArcGIS与AutoCAD结合在1:50 000数据库更新工程中的应用

由于GIS软件平台与CAD软件平台各自具有的优势不一样,如何把ArcGIS和AutoCAD相结合,利用各自优势,快速有效地进行地形图数据库内业编辑、数据分析;本文重点讨论了GIS和CAD数据交换的问题.     

发扬夏坚白院士精神,倡导尊重知识、重视知识产权的行业之风

前不久,报章上出现了这样一条消息:国家信息产业部、国家版权局、商务部、财政部四部委联合下发了<关于计算机预装正版操作系统软件有关问题的通知>.根据通知精神,从现在开始没有预装正版操作系统的PC产品将无法上市销售.     

评Seeber教授所著的《Satellite Geodesy》(卫星大地测量学)

德国汉诺威大学土木工程与测量系地球测量研究所Guenter Seeber教授所著的《SatelliteGeodesy》(卫星大地测量学)第2版已于2003年由德国Walter de Gruyter出版社在柏林出版.本书的第1版于1993年由该出版社出版,都是用英文写成.第1版曾由国家地震局地震研究所赖锡安教授等译成中文于1998年由地震出版社出版.第2版与第1版之间相隔恰好10年,10年来卫星大地测量领域有了很大的发展和变化,Seeber教授以其深邃的眼光、严谨的学风和渊博的知识全面修订和扩展了第1版.本文结合第1版,将第2版的主要内容和特色介绍给我国读者,希望能对广大测绘同行有所裨益.     

卷首语

由原《测绘学院学报》改版后的《测绘科学技术学报》已经面世一年了. 在过去的2006年里,本刊得到了编委会顾问、编委、通信编委及国内外同行和学者的厚爱、关心和支持,内涵有了进一步扩展,质量有了进一步的提高,被评为"首届中国高校优秀科技期刊".     

基于VBA的Excel测量程序开发技术

基于VBA开发Excel测量程序具有简便、高效和通用的特点,程序的使用具有直观、实时、动态、灵活、交互性与图形功能强等明显的优势.由于Office软件使用的普遍性及其组件之间数据良好的交互性和共享性,Excel在数据处理与相应报告的生成等方面更具优势.以开发实例介绍使用VBA开发Excel测量程序的主要技术方法.     

搜酷

强悍的摄像机作为索尼XR系列摄像机的开篇之作,HDRXR520E集众多项级配置于一身,采用了在低光照环境下有着出色表现的Exmor R CMOS感光元件,     

An approach to use of aerial photos in small scale soil mapping based on experience of Jodhpur district,Rajasthan

Photocharacteristics of some of the dominant soils were already known from experience within and outside the survey area. Using these known photocharacteristics an interpretation was carried out enabling a coverage of nearly 65% of the total area of the district. Simultaneously, the remaining 35% area split into various sized patches was photo-analysed and the characteristics noted. Thereafter field traversing was taken to carry out checking of the already interpreted area and interpretation of photo-analytical units and a few uncertain areas. This method of partial interpretation-cum-analysis in the first stage itself was found fully workable for the present area. Interpretations of some of the new dominant analytical units are reported.     

Assessment of a spatial multi-criteria evaluation to site selection underground dams in the Alborz Province,Iran

Most part of Iran is arid and semi-arid; thus in most parts of the region, groundwater is the only source of water. This research presents a method based on a spatial multi-criterion evaluation (SMCE) for designing possible sites of underground dams and ranks them according to their suitability. The method was tested for siting underground dams in the Alborz Province, Iran. At first, screening algorithm was applied using exclusionary criteria, and thirty-one potential areas were recognized in the study area. In the next step, a suitable gorge or valley was recognized using the combination of basic maps and extensive field surveys (long axis of tank level) in each potential area. Subsequently, the analytical hierarchy process was used as a powerful tool for decision-making in the SMCE in order to evaluate different criteria for underground dam sites. SMCE techniques were then applied to combine the criteria, and obtain a suitability map in the study area. These sites were then compared and ranked according to their main criteria such as water, storage, axis and socio-economics. All these criteria were assessed through geographical information system modelling. This method shows passable results and could be used for site selection of underground dams in other regions of Iran.     

Application of fuzzy AHP method to IOCG prospectivity mapping: A case study in Taherabad prospecting area,eastern Iran

Using fuzzy analytical hierarchy process (AHP) technique, we propose a method for mineral prospectivity mapping (MPM) which is commonly used for exploration of mineral deposits. The fuzzy AHP is a popular technique which has been applied for multi-criteria decision-making (MCDM) problems. In this paper we used fuzzy AHP and geospatial information system (GIS) to generate prospectivity model for Iron Oxide Copper-Gold (IOCG) mineralization on the basis of its conceptual model and geo-evidence layers derived from geological, geochemical, and geophysical data in Taherabad area, eastern Iran. The FuzzyAHP was used to determine the weights belonging to each criterion. Three geoscientists knowledge on exploration of IOCG-type mineralization have been applied to assign weights to evidence layers in fuzzy AHP MPM approach. After assigning normalized weights to all evidential layers, fuzzy operator was applied to integrate weighted evidence layers. Finally for evaluating the ability of the applied approach to delineate reliable target areas, locations of known mineral deposits in the study area were used. The results demonstrate the acceptable outcomes for IOCG exploration.     

Coupling of remote sensing data and environmental-related parameters for dengue transmission risk assessment in Subang Jaya,Malaysia

In Malaysia, the endemic level of dengue fever (DF) has already changed morbidity indicators, and the magnitude of these incidences in the last few years has surpassed the incidences of all other diseases of compulsory notification. The reasons for the dramatic emergence of DF are complex and not well understood. There are many factors that contribute to the epidemiological conditions that favour viral transmission by the main mosquito vector. This study, therefore, is filling this gap by analysing the impact of dengue incidence at a local (Subang Jaya) scale using environmental factors. Meteorological data and land-use pattern were consolidated using geographic information system (GIS) and its components as an analytical tool. We have shown that weather variables (relative humidity, temperature and precipitation) have significant correlation with DF incidence with seasonal variation. Besides land-use pattern, DF incidence shows the higher distribution in the residential area, followed by commercial and industrial area. This is due to the higher population density in residential area as well as favourable places for the breeding of dengue-carrying Aedes mosquitos created by humans in the residential area, especially one-storey houses. The analysis on the trends of DF incidence towards various housing types indicate that most of the victims’ houses fall into interconnection houses and mixed houses types compared to the independent houses area. The outcome driven from this analysis suggested that each character of the environmental factors has their own risk towards dengue incidence. In line with that, it is possible to develop a dynamic model of DF transmission using the knowledge produced by this comprehensive time series data and the results provided by the different analyses.     

The Scope and Conceptual Content of Analytical Cartography

Over the last three decades analytical cartography has grown from Tobler's concept of "solving cartographic problems" into a broader and deeper scientific specialization that includes the development and expansion of analytical/mathematical spatial theory and model building. In many instances Tobler himself has led the way to these new insights and developments. Fundamental concepts begin with Tobler's cartographic transformations; Nyerges' deep and surface structure and data levels; and Moellering's real and virtual maps; the sampling theorem; and concepts of spatial primitives and objects. This list can be expanded to include additional analytical concepts such as spatial frequencies, spatial surface neighborhood operators, information theory, fractals, Fourier theory, topological network theory, and analytical visualization, to name a few. This base of analytical theory can be employed to analyze and/or develop such things as spatial surfaces, terrain analysis, spatial data schemas, spatial data structures, spatial query languages, spatial overlay and partitioning, shape analysis, surface generalization, cartographic generalization, and analytical visualization. More analytical uses of theory, strategies of analysis, and implementations are being developed and continue to multiply as the field continues to grow and mature. A primary goal is to expand the mathematical/analytical theory of spatial data analysis, and theory building and analytical visualization as analytical cartography takes its place in the geographic information sciences. The research future for this area appears very bright indeed.     

EDMI测距房产面积测量精度估算方法的研究

本文研究了用EDM(电子测距)边长的精度估算方法;用等权代替法估算界址点最弱点的点位中误差;由坐标解析法界址点与面积的误差传播关系、导出了面积精度估算的具体计算公式。对于实际的房产面积精度的合理估算具有一定的现实意义和指导作用。     

The change of land use/cover and characteristics of landscape pattern in arid areas oasis: An application in Jinghe,Xinjiang

This paper uses 3S technology in macroscopic. Combining the integrated technology of ecological quantity analytical method with GIS technology through ArcGIS and Fragstats, the authors study the images of 1972, 1990, 2001, and 2005 and obtained land use data in Jinghe County. Then, the change of land use/cover and landscape pattern had been analyzed in the Jinghe County of Xinjiang. The conclusions were as follows: (1) The trend of LUCC is that the area of oasis expands slowly in nearly 33 years between 1972 to 2005 in Jinghe County. (2) The water area is mainly influenced by Ebinur Lake, so the area expands a little in this period. (3) The area of salinization-land expands at first and reduces later. The area of sand land decreases and the other land class increases, while the probability of transfer is always high. (4) Landscape change is also obvious throughout the decades. Overall, landscape density increases, the largest path index decreases at first and expends later, the weight area index decreases, and the shape of landscape becomes regulated. The nearest distances, the degrees of reunite, and outspread decreases. It shows that the connection of the main path in 1972 is better than 2005, wherein the patch becomes more complex. From the changes of Shannon’s Diversity Index and Shannon’s Evenness Index, we know that the diversity of landscape and the Interspersion Juxtaposition Index increase. The degree of diversity landscape and fragmentation increase also shows that the land uses become more complex. All in all, it is essential to intensify the spatial relationships among landscape elements and to maintain the continuity of landscape ecological process and pattern in the course of area expansion.     

解析延拓高阶解的推导方法与比较分析

利用迭代求导法、直接求导法推导了解析延拓高阶解公式,并与经典递推方法进行了比较分析。利用迭代求导法得到了重力异常径向导数在球近似下的通用递推公式,该公式表明,解析延拓的经典递推求解方法实际上是忽略小项的近似,在忽略小项后,迭代求导法与递推法的形式是一样的。虽然直接求导法可以提高计算速度,但利用5°×5°实验区的重力数据进行解析延拓实验的结果表明,直接求导法获得的犵2项数值较其他方法偏小0.1～0.4mGal,这种差异的产生主要由于计算误差引起的。     

西南三江地区矿产资源遥感综合预测方法

详细阐述了矿产资源遥感综合预测方法的工作程序、控矿要素的数字化分析与遥感找矿模型的建立,以及遥感矿产的综合分析评价方法与应用等,并以西南三江中段遥感综合预测成果佐证了矿产资源遥感综合预测方法在矿产资源预测中能使野外调查工作更具预见性和目的性,从而大大缩短了矿产资源调查的工作周期。     

The effect of topography on the determination of the geoid using analytical downward continuation

The method of analytical downward continuation has been used for solving Molodensky’s problem. This method can also be used to reduce the surface free air anomaly to the ellipsoid for the determination of the coefficients of the spherical harmonic expansion of the geopotential. In the reduction of airborne or satellite gradiometry data, if the sea level is chosen as reference surface, we will encounter the problem of the analytical downward continuation of the disturbing potential into the earth, too. The goal of this paper is to find out the topographic effect of solving Stoke’sboundary value problem (determination of the geoid) by using the method of analytical downward continuation. It is shown that the disturbing potential obtained by using the analytical downward continuation is different from the true disturbing potential on the sea level mostly by a −2πGρh 2/p. This correction is important and it is very easy to compute and add to the final results. A terrain effect (effect of the topography from the Bouguer plate) is found to be much smaller than the correction of the Bouguer plate and can be neglected in most cases. It is also shown that the geoid determined by using the Helmert’s second condensation (including the indirect effect) and using the analytical downward continuation procedure (including the topographic effect) are identical. They are different procedures and may be used in different environments, e.g., the analytical downward continuation procedure is also more convenient for processing the aerial gravity gradient data. A numerical test was completed in a rough mountain area, 35°<ϕ<38°, 240°<λ<243°. A digital height model in 30″×30″ point value was used. The test indicated that the terrain effect in the test area has theRMS value ±0.2−0.3 cm for geoid. The topographic effect on the deflections of the vertical is around1 arc second.